Draft rigging



Feb. 18, 1941. D. s. BARROWs DRAFT RIGGING Filed Nov. 12, 1957 Y 2 Sheets-Sheet 1 s w a m e m 2 5% 0 2 /2L /a 5 7 5 2 Patented Feb. 18, 1941 UNITED STATES DRAFT RIGGING Donald S. Barrows, Rochester,-N. assignor to the Symington-Gould Corporation, Rochester, N. Y., a corporation of Maryland Application November 12, 1937, SerialNo.174,253

21 Claims.

The present application is a continuation- 4npart of my copending application for Draft rigging, SerialNo. 711,247, filed February 14, 1934.

The invention pertains to draft rigging for a railway vehicle and more particularly to that portion thereof known as a draft gear which is employed to cushion or dampen the draft and buffing shocks transmitted to the vehicle during service.

The principal object of the invention is the provision, in a railway draft rigging, of, a draft gear comprising a casing or housing having associated therewith transversely acting springs and shoe means and longitudinally acting wedge and spring means to form. a structure capable of frictionally and resiliently dampening or absorbing draft and buffing shocks.

Another object of the invention is the provision of a draftgear or cushioning unit comprising a housing formed of longitudinal walls, a plurality of laterally movable friction shoes positioned within the housing, the movement of said shoes being resiliently resisted by longitudinally disposed andtransversely acting sets of springs interposed between each friction shoe and the adjacent wall of the housing, said shoes having a pair of longitudinally acting wedge members frictionally associated therewith adapted to force the shoes apart; and said wedge members reacting against a longitudinallydisposed spring. The wedge members preferably are provided with outstanding shoulders or lugs thereon for engaging the housing and thereby limiting the longitudinal outward movement of the wedge members with respect thereto.

A further object of the invention is the provision of a. draft gear or cushioning unit comprising a housing formed with longitudinal walls connected integrally at their respective ends by transverse end walls and intermediate their ends by a bulkhead or partition wall to form two compartments therein, one end wall being provided with an aperture for the introduction to One of the pockets of wear or housing protective plates, transversely actingsprings andfrictlon shoes and longitudinally acting spreader or follower wedge members, the other end wall and the partition being provided with an aperture for the reception of a wedge member actuating spring or longitudinally acting resilient means; the last-mentioned end wall having a removable means associated therewith forming an abutment for the wedge member spring.

These and numerous other objects will become apparent froman inspection of the accompanying drawings which disclose. an exemplary form of the present invention and wherein, considered generally:

Figure l is a view of a draft gear embodying a form of the present invention shown partially in side elevation and partially in longitudinal section.

Figure 2 is a sectional longitudinal view corresponding somewhat to the sectional view disclosed by Figure 1, except that the draft gear is illustrated partly compressed, that is, all of the associated elements are disclosed in a position after a predetermined travel or compressive movement of the gear, while the structure of Figure 1 is illustrated as completely expanded. Figure 3 is a longitudinal sectional view taken along the lines 3-3 of Figure 1 and looking in the direction of the arrows.

Figure 4 is a cross sectional view taken along the'lines 44 of Figure 3 and looking in the direction of the arrows.

Figure 5 is an enlarged and partial end elevational view taken along the lines 5--5 of Figure 3 and looking in the direction of the arrows. Figure 6 is an enlarged View of a modification ofythe invention and corresponding in part to Figure 3 except that the housing is provided with a removable wear plate. Referring now more particularly to the exemplary construction illustrated in the drawings, wherein like reference characters indicate like parts, the draft gear, generally designated by the numeral I, comprises, a housing or casing 2 formed by a pair of spaced longitudinally extending or oppositely disposed bearing walls 3 and a pair of spaced longitudinally connecting walls 4 integrally joining the adjacent edges of the bearing walls. The housing I is provided on the one end thereof with transverse end walls 15 extending inwardly of the housing from the bearing walls and between the connecting walls to form a relatively restricted open end 6. The transverse end walls 5 have their free opposing ormeeting edges thereof spaced to form an aperture 1 to within thehousing which, in its longest dimension, corresponds preferably to the inner dimension of the housing. The other end of the housing is provided with a single integrally formed wall 8 joining the bearing and connecting walls to form a relatively closed housing end 9. A transverse bulkhead or partition Ill extends between and integrally joints the longitudinal walls at a location intermediate the ends thereof to divide the housing into compartments or pockets II and IL. The pocket H preferably forms a receptacle for the cushioning or shock-absorbing elements, hereinafter referred to in detail, and the pocket or compartment I2 desirably forms a receptacle for a portion of a resilient element of the draft gear as well as a spacing means in order to add sufficient length to the draft gear and thereby make it applicable to a standard draft gear pocket of a railway vehicle.

The cushioning elements or shock-absorbing structure of the draft gear preferably comprises transversely acting spring means I3 adapted to bear against a pair of inner wedges or shoes I4, a longitudinally acting spring I5, and a central shoe spreader or intermediate wedge I A pair of housing protective and removable wear plates I'I, preferably angle or L-shaped in section, is positioned within the compartment II,,and each has a longitudinal leg portion I8 in intimate contact with the corresponding bearing wall 3 and a transverse leg I9 associated with the adjacent end wall 5. A removable wear and partition plate 20 is also arranged within the compartment or pocket II and in bearing relation with the partition I I] and thereby, considered together with the plates I'I, forms a replaceable inner housing protective means,

The oppositely acting or transversely spaced springs I3 are located in the compartment II and extend longitudinally of the draft gear. The springs I3 desirably take the form of a set of curved spring plates or leaves having the concave surface 2| thereof facing outwardly of the housing and the ends of the outermost plate I3 bearing against the wear plate I1. Nibs or convol-uted portions 22 are provided adjacent the end of each plate and form interlocking means to prevent the plates from assuming other than a normal relation with respect to one another in a group or set. The nibs, provided on the spring plate I3 adjacent and bearing against the wear plate II, extend into aperatures or notches 23 in the wear plate, and by this arrangement the springs and wear plates are restricted against relative lateral shifting.

Interposed between the springs I3 is a pair of inner counterpart Wedges or shoes I4 adapted to be urged away from one another transversely of the housing by means of a longitudinally acting intermediate or spreader wedge I6. The shoes I4 have an end surface 24 in bearing relation with the partition plate 20 and are adapted to frictionally engage the plate upon any movement of the shoes with respect to the plate.

As the springs I3 are flexed or compressed by the transverse movementof the shoes toward the bearing walls, each of the shoes is preferably provided with a concave spring-engaging surface 24 bearing against the inner convex surface of the associated spring. The surface 24 is cylindrically concave about a radius desirably greater than the normal curvature of the springs, so that the surface may substantially conform to the final curvature of the springs upon the flexure or compression thereof when they have been urged through their required or predetermined distance of travel. This curved surface 2t has been provided to eliminate the possibility of the contraflexure of the spring plates, which would materially reduce the fatigue life of the springs. It will be appreciated that if the spring-engaging surface of the shoes were formed to present an even or plane surface the spring plates would, during the compressive flexing movement of, the plates, assume not a single curvature of increased radius but, in contradistinction thereto, a triple curvature or sinuous form. While the outer ends of the spring plates would, under such condition, maintain a semblance of the original curvature, the intermediate portion of the plates would, however, be flexed or urged in a curvature counter to the normal or original curvature of the spring. In other words, this condition would present two spaced points of contraflexure, and consequently a plurality of relatively short spans with the portions of the plates therebetween more highly stressed, which would result in diminishing the fatigue life of the springs.

The intermediate or spreader wedge I6, desirably formedof two counterpart members 25 to facilitate assembly, occupy the aperture 1 and extend outwardly of the housing beyond the transverse end walls 5. Each of the wedge members 25 have an outer surface 26 spaced from the walls 5 a distance substantially equal to the desired or predetermined compressive movement or travel of the draft gear. The surfaces 26 are adapted to engage a draft gear follower block or draft yoke, neither of which are illustrated.

A portion of the wedge members extending outwardly of the housing is provided with confrontingly disposed or juxtapositioned surfaces 26 which are'adjacent and extend in the direction of the longitudinal axis of the housing. As the surfaces 26 are thus perpendicularly arranged with the relation to the outer surfaces 26 it will be appreciated that any angular movement of the wedge members laterally or away from the longitudinal axis of the housing will be restricted by the surfaces 26 The inner portion of each wedge member is provided with a sloping surface 2'! which, by considering the combined members as a single element, are converging and oppositely disposed with respect to one another. The sloping wedge surfaces 2''! are arranged to engage coplanar or correspondingly sloping surfaces 28 provided on the shoes I4. By this arrangement of elements it will be clearly appreciated that, upon any movement of the wedge members in a longitudinal direction inwardly of the housing, the said members will frictionally engage and'force the shoes apart or toward the bearing walls 3. The transverse movement of the shoes will create frictional forces between the shoes and partition plate, and this movement of the shoes will also 0 be resiliently resisted by means of the springs I 3.

In order to dispense with tie bolts or retaining rods for maintaining the draft gear in assembled relation, each Wedge member is desirably provided with an outstanding shoulder or lug 29 positioned adjacent the inner extremity of the wedge-members and extending into longitudinally disposed slots or elongated apertures 30. The slots are provided in the connecting walls 4 and are of such length that an unrestricted and full compressive movement of the draft gear is permitted, The lugs are adapted to engage the connecting wall at the forward extremity of the slots to. limit or stop the movement of. the wedge members outwardly of the housing. In actual practice, as is well known to those of the art, the draft gear pocket in a railway vehicle is, at times, formed over-size, that is, the distancebetween the front and rear draft gear-abutments-is sometimes made greater than the required or permissive dimension. If, therefore, the length of the draft gear is gauged to the required dimension and the gear is then applied to a: vehicle having an over-sized pocket, it will be appreciated that the difference in dimensions will result in the draft gear floating in the pocket or lying out of intimate contact with the front and rear abutments. In order to overcome this possible and undesired condition, a suitableclearance, indicated as at 30 is provided between :the lug and the adjacent end portion of the slot in a draft gear of normal length so as to permit the draft gear to assume a longitudinal dimension corresponding to the draft gear pocket of a vehide.

The clearance at. ill has a two-fold purpose of function, in that, during assembly of the gear with a vehicle, the gear may be pine-com- "greater than the inner dimension or clear opening of the housing, each wedge member is provided with an inclined or tapered surface 31,

most clearly illustrated in Figure 3 and forming an inward continuation of the juxtapositioned surfaces 26, so as to permit the assembly of the wedge members with the housing. The. tapered surface of one wedge member is positioned adjacent or facing the tapered surface of the other wedge member so that, considering the wedge members in their assembled relation, the tapered surfaces desirably start on or adjacent the longitudinal axis of the draft gear and extend away from one another toward the connecting walls 4.

After the wear or protective plates l1 and 20,

the springs i3 and the shoes 14 have been introduced or inserted into the pocket I l through the aperture 1, each wedge is tilted to an abnormal position with the tapered surf-aces 3 coplanar with the longitudinal axis of the draft gear. The wedges in this relation are then threaded through the aperture 1 until the lugs are aligned with the slots 30, at which time the wedge members are straightened or arranged in their normal position, thereby moving the lugs 29 into the slots 30 and in the longitudinal plane of the connecting walls 4.

The resistance or wedge release spring t5, preferably formed as a coil or helical spring, extends longitudinally of the housing through suitable apertures provided in the partition wall, partition plat-e, shoes and wedge members, respectively. The one end of the spring abuts an inner surface 32 of the wedge members to resiliently force the members outwardly of the housing or resiliently resist the movement of the wedge members inwardly of the housing. The spring desirably encircles a semi-circular boss 33 provided on each of the wedge members and thereby prevents the members from spreading.

The spring I5 is introduced into the housing through a centrally disposed aperture 34 provided in the wall 8 of the closed end of the housing and is confined therein by means of a retainer 3b which is positioned in the aperture and removably or detachably associated with the wall 8. The spring retainer is preferably circular in general form, having a surface 3-6 thereof in the plane of the wall 8 so as 'to present an even or smooth abutting surface for an associated follower plate or stop means (not shown). The inner portion of the retainer is provided with a boss 31 which projects intothe spring 15 and thereby forms a positioning or anchorage means for the spring to prevent a lateral shiftingthereof. The retainer has outstanding spokes or shear lugs- 38 spaced along the peripheral edge thereof, which are norm-ally positioned in arrear of the wall 8, Spaced fingers 39, projecting inwardly of the housing from the wall 8an-d integrally formed therewith, lie adjacent at least one of the lugs38 to prevent an unwarranted or accidental displacement of the retainer.

The retainer is assembled with the draft gear by aligning the lugs 38 with suitable or correspondingly formed notches 40 in the wall 8 which are connected with the aperture 34 The retainer is then urged inwardly of the housing,

whereupon a rotative movement of the retainer will position one of thelugs 38 between the fingers 39 and all of the lugs in arrear of the wall 8. t

By now considering in detail the modification of the invention illustrated by Figure 6, it will be observed that the connecting wall 4 of the housing I is, similarly to the disclosures in Figures 1 to 5, inclusive, provided with a longitudinally disposed slot 30* adapted to receive a restricting. or arresting lug portion '29 of a wedge member N6. N clearance is provided between the lug, when in its normal position, and the associated end of the slot, and in such a structure the lug is adapted to intimately contact the housing of the connecting wall to limit or arrest the outward movement of the wedge member with respect to the housing. However, in order to protect the connecting wall at the lug-engaging portion thereof 'a removable wear plate 4| is provided with a web 4-2 thereof interposed between the lug and connecting wall. The wear plate is retained in position by means of an overlying flange 43, angularly disposed with respect to the web 42 and engaging the outer surface of the connecting wall, and an underlying flange 4 4 engaging the inner surface of the connecting wall; The underlying flange 4 4 preferably terminates in a reentrant flange extending into a recess 46 formed in the connecting wall and spaced from the adjacent end portion of the slot 30*. I

lit will, of course, be understood that various changes and alterations in construction may be made to the illustrated form of the invention without departing from within the spirit and scope of the appended claims.

I claim:

1. In a draft gear, in combination, a housing comprising spaced longitudinal bearing and connecting walls joined intermediate their ends by a transverse wall, shoes movable laterally in said housing and bearing against said transverse wall, leaf spring means interposed between said bearing walls and shoes, wedges movable longitudinally of said housing and having tapering friction surfaces interposed between said shoes, helical spring means acting between said wedges and housing for resisting movement of said wedges into the housing, outstanding lugs on said wedges extending into slots in said connecting walls to normally prevent the disassembly of said wedges and housing, and surfaces on each wedge disposed at an angle to the plane of the friction surfaces thereof for permitting the assembly of said wedges at an angle to the longitudinal axis of said housing.

2. In a draft gear, in combination, a housing comprising spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, resilient means interposedbetween said tudinally of said housing and each having wedging surfaces adapted to frictionally engage said shoes, spring means acting between said wedges and housing for urging said wedge outwardly of the housing,'lugs formed on said wedges and extending into slots in said connecting walls, and surfaces on said wedges commencing adjacent the longitudinal axis of the draft gear and inclined outwardly therefrom for permitting assembly of said wedges with said housing.

3. In a draft gear, in combination, a housing comprising spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, resilient means interposed between said bearing walls and shoes, wedges movable longitudinally in said housing and having a normal over-all width greater than the inner width of said housing, wedging surfaces on said wedges in intimate contact with and adapted to frictionally engage correspondingly formed surfaces on said shoes, resilient means for urging said wedges outwardly of the housing, and inclined surfaces on said wedges for permitting assembly of said wedges with said housing at an angle to the longitudinal axis of said draft gear.

4. A cushioning mechanism comprising a housing having spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, plate springs interposed between said shoes and bearing walls, wedges movable longitudinally of the housing and acting between said shoes for urging them apart, a coil spring associated with said housing and Wedges for resilient ly resisting the movement of the wedges inwardly of the housing, said coil spring locking said wedges against angular movement with respect to one another, outstanding lugs on said wedges extending into slots in said connecting walls for limiting the outward movement of said wedges, the normal over-all width of said wedges being greater than the inner width of said housing, and

juxtapositioned surfaces on said wedges terminating in inclined surfaces for permitting assembly of said wedges with said housing.

5. A draft gear comprising a housing having spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, longitudinally disposed and transversely acting resilient means interposed between said shoes and bearing walls, wedges movable longitudinally of said housing and acting between said shoes for urging the latter apart, longitudinally acting spring means associated with said housing and wedges for urging the latter outwardly of the housing, integral outstanding lugs on said wedges extending into slots in said connecting walls intermediate the ends thereof, said lugs being adapted to engage said connecting walls for limiting the outward movement of said wedges, the normal over-all Width of said wedges being greater than the inner width of said housing, and inclined surfaces on said wedges for'permitting assembly of said wedges with said housing.

6. In a draft gear, in combination, a housing having spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, a transverse partition in said housing for restricting longitudinal movement of said shoes, resilient means interposed between said bearing walls and shoes, longitudinally movable wedges interposed between and adapted to frictionally engage said shoes upon relative movement there- 'between, spring means acting between said wedges and housing .for urging said wedges outwardly, of the housing, integral meansoutstanding froinsaid wedges and movablyassociated with said connecting walls for limiting outward movement of said wedges with respect to the housing, and sloping surfaces on said wedges for permitting assembly of said wedges with said movement thereof, wedges movable longitudinally of said housing and acting between said shoes for urging them apart, spring means associated with said housing and said wedges for resiliently resisting the movement of the wedges inwardly of said housing, outstanding lugs on said wedges extending into slots in said connecting walls for limiting the outward movement of said wedges, the normal over-all width of said wedges being greater than the inner width of said housing, and tapered surfaces on said Wedges for permitting assembly of said wedges with said housing.

8. A cushioning mechanism comprising a housing having spaced longitudinal bearing and connecting walls, a transverse end wall integrally joining said bearing and connecting walls, a pair of shoes movable laterally in said housing and restricted against longitudinal movement by a partition formed integrally with said housing, arcuate springplates interposed between each of said shoes and bearing walls, said shoes having a concave surface thereof bearing against a convex surface of said. spring plates and being of greater radius than the normal curvature of said plates so as to prevent contrafiexure of said plates upon a spring compressive movement of said shoes, a pair of wedges movable longitudinally of said housing and acting between said shoes for urging them laterally of the housing, a coil spring engaging said wedges for urging them outwardly of the housing, and a coil spring retainer associated with said coil spring and removably associated with said end wall.

9. In a'draft gear, in combination, a housing having spaced longitudinal bearing and connecting walls, a transverse end wall integrally joining said bearing and connecting walls, a .pair of shoes movable laterally in said housing, arcuate spring plates interposed between each of said shoes and bearing walls, said shoes having a concave" surface thereof bearing against a convex surface of said plates and being of greater radius than the normal curvature of said plates so as to prevent contraflexure of said plates upon a spring compressive movement of said shoes, a pair of wedges movable longitudinally of said housing and acting between said shoes for urging them laterally of the housing, said wedges each having an integral lug adapted to engage, and positioned in thelongitudinal plane of, an associated connecting wall, sloping surfaces on said wedges for permitting assembly of said wedges with said housing, a coil spring engaging said wedges for urging them outwardly of the housing, and a coil spring retainer removably associated with said end wall.

10. A cushioning mechanism comprising a housing having two pairs of spaced longitudinal side walls connected together adjacent one end thereof by a transverse end wall, a pair of laterally movable shoes in -said housing, laterally acting springs interposed between said shoes and one pair i of-side walls for resiliently resisting the lateral movement of said shoes, wedge members having an outer portion thereof extending beyond the housing and an inner portion provided with inclined surfaces in bearing relation with correspondingly'formed surfaces-on said shoes,

integral means onsaid wedges adapted to engage.

the other pair of side walls for limiting the outward vmovement of said wedges with respect to the housing, a longitudinal spring engaging said wedges for urging them outwardly of the housing, and-a longitudinal spring retaining means removably associated with said end wall.

11; A cushioning mechanism comprising a housing having two pairs of longitudinal side walls, lateral walls extending inwardly of the housing from said longitudinal walls at one end thereof to form a restricted opening in said housing, resiliently restricted and laterally movable shoes in said housing, a transverse partition extending between said longitudinal walls for restricting longitudinal movement of said shoes, wedges positioned in said restricted opening and arranged to frictionally engage said shoes upon longitudinal movement of said wedges, a longitudinally acting spring engaging said wedges for resisting movement of said wedges inwardly of the housing, integral means on said wedges mov--v ably associated with one pair of side walls for limiting outward movement of said wedges with respect to the housing, a transverse wall extending between the other end of said side walls, and a removable means associated with said transverse wall for retaining said longitudinally acting spring within the housing.

12. In a draft gear, in combination, a housing comprising spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing, a transverse partition in said housing for restricting longitudinal movement of said shoes, a wear plate interposed between said shoes and partition, said wear plate being frictionally engaged by said shoes upon relative movement therebetween, leaf spring means interposed between said bearing walls and shoes, longitudinally movable wedges interposed between said shoes, spring means acting between. said wedges and housing for urging said wedges outwardly therefrom, integral lugs on said wedges extending into slots in said connecting walls, and tapered surfaces on said wedges for permitting assembly of said wedges with said housing.

13. Cushioning mechanism comprising a housing having two pairs of spaced longitudinal side walls connected together adjacent one end thereof by an end wall, a pair of laterally movable shoes in said housing, laterally acting springs interposed between said shoes and one pair of side walls for resiliently resisting the lateral movement of said shoes, wedge members having inclined surfaces in bearing relation with correspondingly formed surfaces on said shoes, a coil spring engaging said wedges for urging them outwardly of the housing, integral means on said wedges adapted to engage the other pair of side walls for limiting the outward movement of said wedges with respect to the housing, an aperture in said end wall, and a coil spring retainer removably associated with said end wall; said retainer having outstanding lugs adapted to be positioned inwardly of the housing and in bearing relation with said end wall.

14. In a draft gear, in combination, a housing comprising spaced longitudinal bearing and connecting walls shoes movable laterally in said housing,-a transverse partition in said housing for restricting longitudinal movement of said shoes, a wearplate interposed between said shoes and partition, said wear platebeing f-rictionally engaged by said shoes upon relative movement therebetween, leafspring? means interposed between 'said 'bearingwalls and shoes, longitudinally movable wedges interposed between said shoes, said wedges being provided with friction surfaces coplanar and in intimate contact with correspondingly formed surfaces on said shoes, spring means acting between said wedges and housing for resiliently resisting the movement of said wedges inwardly of the housing, lugs on said wedgesextending into slots in said connecting walls, and surfaces on each wedge disposed at an angle to the plane of said friction surfaces for permitting the assembly of said wedges at an angle to the 'longitudintalaxis of said housmg. I l

15. A cushioning mechanism comprising a housing having slots provided in oppositely disposed walls, a pair of elements movable longitudinally of said housing, means outstanding from eachelement and extending into an associated housing slot to normally prevent the disassembly l of said elements and housing, and angularly disposed faces on said elements to facilitate the assembly of said elements with said housing. i

16. A draft gear, in combination, a housing member comprising spaced bearing walls and a transverse wall, shoes movable laterally in said housing and reacting longitudinally of the housing against said transverse wall, spring means interposed between said shoes and bearing walls,

a wedge member movable longitudinally in said housing member, surfaces on said wedge membar in bearing relation with correspondingly I spaced longitudinally from said intermediate wall. shoes movable laterally in said housing and reacting longitudinally of the housing member against said transverse wall, spring means interposed between said shoes and bearing walls, a wedge member movable longitudinally in said housing member, surfaces on said wedge member in bearing relation with correspondingly formed surfaces on said shoes, resilient means extending through an aperture in said intermediate wall and reacting against said end wall and wedge member for urging the latter outwardly of said housing member, apertures in said housing member, and means normally positioned in said apertures and associated with one of said members for limiting the outward movement of the housing resiliently resisted by elements reacting against said bearing walls, lugs outstanding from said wedge member extending into apertures in said connecting walls for limiting the movement of said wedge member outwardly of the housing, spring means bearing against said wedge member, and a spring means retainer positioned in said end wall aperture, said retainer having outstanding means normally positioned inwardly of the housing and in bearing relation with said end wall.

19. A draft gear comprising a housing having bearing walls joined adjacent one end thereof by an apertured end wall, a wedge member movable longitudinally of said housing and having a movement thereof inwardly of the housing resiliently resisted by elements reacting against said bearing walls, means associated with said housing and wedge member for limiting the movement of said wedge member outwardly of the housing, spring means bearing against said wedge member, a spring means retainer positioned in said end wall aperture, outstanding means on said retainer normally positioned inwardly of the housing and in bearing relation with said end wall, and means on said end wall for maintaining said retainer in a predetermined position.

20. In a draft gear, in combination, a housing, shoes positioned within said housing, spring means resisting movement of said shoes transversely of said housing, and Wedge means interlocked with said housing and adapted to actuate said shoes, said wedge means being of an overall width greater than the clear opening into said housing and comprising a. pair of members having juxtapositioned surfaces terminating inwardly of the housing in tapered surfaces for permitting assembly of said wedge means and housing.

21. In a draft gear, in combination, a housng member comprising spaced longitudinal bearing and connecting walls, shoes movable laterally in said housing member, means within said housing for restricting longitudinal movement of said shoes relative to said housing member, arcuate spring plates interposed between said bearing walls and shoes, said shoes having concave surfaces thereof bearing against a convex surface of each of said spring plates and being of greater radius than the normal curvature of said plates so as to prevent contraflexure of said plates upon a spring compressive movement of said shoes, a wedge unit movable longitudinally in said housing member, surfaces on said wedge unit in intimate contact with and adapted to frictionally engage correspondingly formed surfaces on said shoes, resilient means for urging said wedge unit uotwardly of the housing member, and lugs on said wedge unit adapted to react against said housing to limit the outward movement of said wedge unit in respect to said housing member; said wedge unit being arranged and constructed so as to allow the assembly and disassembly of said housing member and wedge unit.

DONALD S. BARROWS. 

